Delayed sequelae of vertebral artery dissection and occult cervical fractures.

We report three patients who developed delayed (ie, more than a week after the injury) symptoms of vertebrobasilar ischemia following motor vehicle accidents. The patients all had angiographic evidence of vertebral artery dissection and, upon further evaluation, occult fractures of the second cervical vertebra that were not detected by simple cervical spine radiography and required polytomography or CT for diagnosis. Vertebral artery dissection can result from occult cervical spine fractures and may present with delayed symptoms of brain ischemia.